A SEARCH FOR DIFFUSE EMISSION OF UHE GAMMA-RAYS IN SOUTHERN SKY FROM OBSERVATION OF HADRONLESS AIR SHOWERS

The lateral distributions of hadrons in air showers have been determin ed precisely as a function of the core distance, the shower size, the zenith angle and age, and the hadronless showers as candidates of gamm a-ray-initiated air showers can be discriminated with this average lat eral distribution. There is no evidence of the detection of gamma rays from any diffused regions with enough significance, but the arrival d irections of hadronless air showers selected under strict conditions h ave an anisotropy in the equatorial coordinates.